docs: Fix changelog and postgres info for 11.x.

- Fixed misordered changelog entries for version 11.x and 10.3.
- Removed postgres 13 from support table for zulip 11.x.

docs/overview/changelog.md

@@ -13,6 +13,14 @@ log][commit-log] for an up-to-date list of all changes.
 
 _Unreleased_
 
+#### Upgrade notes for 11.0
+
+- PostgreSQL 13 is no longer supported; if you are currently using it, you will
+  need to [upgrade PostgreSQL](../production/upgrade.md#upgrading-postgresql)
+  before upgrading Zulip.
+
+## Zulip Server 10.x series
+
 ### Zulip Server 10.3
 
 _Released 2025-05-15_
@@ -43,14 +51,6 @@ _Released 2025-05-15_
   once.
 - Updated translations.
 
-#### Upgrade notes for 11.0
-
-- PostgreSQL 13 is no longer supported; if you are currently using it, you will
-  need to [upgrade PostgreSQL](../production/upgrade.md#upgrading-postgresql)
-  before upgrading Zulip.
-
-## Zulip Server 10.x series
-
 ### Zulip Server 10.2
 
 _Released 2025-04-15_

docs/production/postgresql-support-table.md

@@ -8,4 +8,4 @@
 | 8.x                  | 12, 13, 14, 15, 16               |
 | 9.x                  | 12, 13, 14, 15, 16               |
 | 10.x                 | 13, 14, 15, 16                   |
-| 11.x                 | 13, 14, 15, 16, 17               |
+| 11.x                 | 14, 15, 16, 17                   |